The bedroom Yolanda wakes up in, in Rowley Regis in the West Midlands, is a shrine to the Baggies: shelves and walls are strewn with pennants, scarves and pictures of players whose careers ended long before she was born. Downstairs her parents, Gordon and Andriana, have a 10th birthday surprise: Uncle Eamon, Yolanda's favourite football-watching companion, has been travelling since 2am from Ireland to take her to today's match against Portsmouth. Between the excitement of seeing Eamon and the anticipation of meeting Jonathan Greening, it's tough to manage any Weetabix.

11.45am

With an entourage that would not shame a Hollywood starlet - including more Irish relatives and next-door neighbour Mick - Yolanda arrives at West Brom's community building, a short walk from The Hawthorns, to the news that Portsmouth are being put up for sale. She may not be able to spell schadenfreude, but she understands the concept. Offered the chance to be mascot at any game, she spurned the Big Four for Pompey - 'because they knocked us out of the FA Cup and I want to get them back'. Yolanda was at Wembley for that semi-final last April; did the result spoil the experience? No, she says sagely: 'It's the luck of the draw, isn't it? You get used to losing.'

12.15pm

The five mascots - three Albion, two Pompey - change into their brand new kit. Everyone looks nervous and the grandness of the occasion threatens to reduce the smallest to tears. Yolanda, however, seems to grow in confidence from the moment she dons the stripes. Heading for a pre-match stadium tour, she shares her secret plan. 'I'm going to drag my feet,' she says, with a daring look. 'I want to take a bit of the turf with me.'

Her predictions are equally bullish. 'I think Scott Carson's going to have a good game today because he's trying to prove he's the number-one goalkeeper in England.' And the scoreline? 'Well, I thought we were going to win, but whenever I go to a game with Eamon, we draw,' she says, with a dark look in his direction. 'So now I'm saying 2-2.'

1pm

On the stadium tour, Yolanda beams for the photo ops - in the dugouts, in the tunnel, by the corner flag, in the interview room - while a paparazzi of proud parents snap on. The club staff ask if there are any questions. Ever-polite, she puts up her hand. 'Have we got a shirt sponsor yet?'

Yolanda wasn't supposed to be a Baggie. Her dad is a die-hard Birmingham fan, Uncle Eamon supports Liverpool, and her cousins like Man United. But a family friend bought her the kit when she was little and entertained her with chants of 'Boing Boing!'; by the age of five, she was at her first match. Little by little she's winning the family over - there's just Nan, the Wolves fan, left to turn.

1.20pm

The parents are left pitchside as the mascots are conducted towards the home dressing room. Each is allowed to have their photo taken with one player and, as they line up in the corridor, they face the tough decision - Ishmael Miller or Scott Carson or Luke Moore?

There's no doubt in Yolanda's mind. Her loyalty to the injured Filipe Teixeira is fierce, although he hasn't played this season. 'We need him to come back and score lots of goals,' she explains, before going off to tell him so.

2.15pm

Mascots need a pre-match warm-up too, so Yolanda changes into her brand new birthday boots and heads on to the pitch for a kickabout. David James, already practising between the posts, boots a couple over; Sol Campbell puts in a gentle tackle on his way to join his team-mates.

Yolanda plays in a football camp every Friday. I wonder who she plays like - Teixeira, by any chance? 'I'm a holding midfielder,' she says. 'My dad says I'm like Michael Carrick.'

3pm

The big moment arrives. As the mascots line up ahead of the teams, Eamon and Mick crane their necks around the mouth of the tunnel to see Yolanda emerge with Jonathan Greening. The Albion captain keeps a paternal eye on his charges as they shake hands with the opposition players, then leads them in a quick kickabout in the centre circle with the match ball. Jan, the club's community officer, sighs happily. 'He's wonderful, Jonathan. He always treats them like they're his own.'

3.05pm

Yolanda heads for her seat in the West Stand - along with one of the Portsmouth mascots, whose best friend is an Albion fan, and who is still in full Pompey regalia. The security man looks unimpressed.

3.40pm

After a couple of shots on goal and a free-kick 10 yards outside the box, Yolanda is frustrated. 'We're good when we're going forward,' she explains, 'but then it all goes downhill because we can't shoot.'

Jonathan Greening comes to the rescue, when a free-kick from Chris Brunt, this one on the edge of the area and directly in front of goal, cannons off the crossbar and Greening scores from the rebound. Yolanda's arms pump up and down along with the Smethwick End in a chorus of 'Boing Boing'.

4.15pm

Yolanda delivered an upbeat half-time verdict - 'We've dominated this half, and we deserve to be 1-0 up' - but now Peter Crouch stretches his long right leg and fires a spectacular shot above Carson's head into the top of the net. Gordon sighs. 'Ah no,' he says. 'Look at her face.' There's more disappointment to come - when Miller is carried off, it's Luke Moore rather than her beloved Teixeira who comes off the bench.

4.40pm

Yolanda decides the referee is definitely against the home side.

4.50pm

The Baggies emerge from the game with a 1-1 draw, the single point not enough to lift them off the bottom of the table. Uncle Eamon is considered to be to blame.

6.40pm

The family arrive home for Yolanda's birthday curry. Sitting in her room, still in full kit, she should be doing homework, but her newly filled autograph book is too distracting. And even if she can't now identify all the squiggles, she knows which one is Teixeira's.